An Assessment of Passive Upper Extremity Exoskeletons during Transthoracic Echocardiograms
Event Type
Poster Presentation
TimeThursday, April 152:00pm - 3:00pm EDT
LocationHospital Environments
DescriptionPrevious studies have noted between 80.9-91% of sonographers feel pain and discomfort related to their work (Claes et al., 2015; Muir et al., 2004; Russo et al., 2002). There have been numerous studies surveying sonographers to assess the prevalence of work-related musculoskeletal disorders (WRMSDs) and while these studies are important to document the prevalence and impact of WRMSDs in sonography, they do not investigate potential interventions to mitigate the problem.

Upper extremity exoskeletons are a potential ergonomic intervention to support sonographers in their work. Exoskeletons are a device that attaches to the body, allowing the user to experience increased physical performance. There have been a limited number of studies documenting the use of passive upper extremity exoskeletons in health care, often focusing on the use of the device in surgical settings. Liu et al. (2018) found participants reported less shoulder pain with the use of upper extremity exoskeletons in laparoscopic surgery task simulations. In this study, we explored the use of an exoskeleton in different area of health care- sonography.

This study moves beyond assessing the prevalence of WRMSDs in sonographers by examining the effectiveness of exoskeletons as a potential ergonomic intervention during transthoracic echocardiograms (TTEs). In this study, four practicing sonographers performed TTE procedures using both right-handed and left-handed scanning techniques, with and without a passive upper extremity exoskeleton (2x2 design). A randomized complete block design was used with participants acting as the blocking variable. Muscle activity data was collected bilaterally on the upper trapezius, anterior deltoids, and medial deltoids using electromyography (EMG). Participants also provided feedback on the use of the exoskeleton.

At the 50th percentile of normalized muscle activity, the exoskeleton significantly reduced the right upper trapezius (p=0.045), left upper trapezius (p<0.001), and the right medial deltoid (p=0.034) activation. There was also a significant interaction between EXOSKELETON and TECHNIQUE for the right anterior deltoid (p=0.0007) and the left medial deltoid (p=0.006), though simple-effects F-test analysis revealed the exoskeleton only reduced muscle activity in left-handed scanning. The exoskeleton tended to reduce muscle activity during left-handed scanning but had little impact on right-handed scanning.

Sonographers liked the support the exoskeleton was able to provide to the scanning arm and shoulder. They reported that wearing the exoskeleton increased their awareness to posture while performing scanning tasks. However, they disliked navigating around patients while wearing the exoskeleton and felt the device may restrict their range of motion.

In this study, it was observed that the exoskeleton provided a greater benefit in reducing muscle activity during left-handed scanning tasks than right-handed scanning tasks. During right-handed scanning, sonographers wrap their right arm around the patient’s torso in order to reach the patient’s chest for imaging. Often, sonographers will rest their right arm on the patient while performing this type of scan. However, the sonographers reported that they were uncomfortable resting their arm on the patient while wearing the exoskeleton, as they did not want the device to cause any discomfort or pain to the patient. This concern likely impacted how the sonographer performed the scan, thus negating the benefits of the exoskeleton during the right-handed scanning condition.

This study provides data to support the hypothesis that upper extremity exoskeletons have positive impacts on muscle activity in sonography, but the type of work and the interaction between the sonographer and patient must be considered in order for the device to provide the greatest benefit. Future work must consider how the exoskeleton can be incorporated into sonography practice in order to provide the physical benefits to the sonographer without negatively impacting the patient experience.

Claes, Frank, et al. “Arm and Neck Pain in Ultrasonographers.” Human Factors, vol. 57, no. 2, 2015, pp. 238–45, doi:10.1177/0018720814547872.

Liu, Shanglei, et al. “Solving the Surgeon Ergonomic Crisis with Surgical Exosuit.” Surgical Endoscopy, vol. 32, no. 1, Springer US, 2018, pp. 236–44, doi:10.1007/s00464-017-5667-x.

Muir, Marylou, et al. “The Nature, Cause, and Extent of Occupational Musculoskeletal Injuries among Sonographers: Recommendations for Treatment and Prevention.” Journal of Diagnostic Medical Sonography, vol. 20, no. 5, 2004, pp. 317–25, doi:10.1177/8756479304266737.

Russo, Andre, et al. “The Prevalence of Musculoskeletal Symptoms among British Columbia Sonographers.” Applied Ergonomics, vol. 33, no. 5, 2002, pp. 385–93, doi:10.1016/S0003-6870(02)00038-8.